1. Field of the Invention
The present invention relates to electrical nerve and muscle stimulation and to electro-stimulation devices and methods for such electro-stimulation and in particular to electro-stimulation devices and methods for use in the electro-medical treatment and electro-stimulation of the muscle and nerve groups associated with pelvic floor musculature and especially although not exclusively where there is dysfunction with this musculature resulting in urinary and/or faecal incontinence.
2. Description of the Related Art
Caring for women with pelvic floor disorders has become an increasingly important component of women's healthcare. These disorders, which include urinary and faecal incontinence, sexual dysfunction as well as pelvic organ prolapse, affect a large segment of the adult female population. One common cause is trauma during vaginal delivery which may result in a variety of pelvic floor complaints; urinary stress and urge incontinence and faecal incontinence are the most frequent and long lasting.
In order to restore function of the pelvic floor muscles after childbirth, women have been encouraged to perform pelvic floor muscle exercises. Pelvic floor muscle exercises (PFME) are a known treatment for exercising muscles which control the urinary function. The theoretical basis of using pelvic floor muscle exercise for the treatment and prevention of stress urinary incontinence is based on the muscular changes that may occur after specific strength training. A strong and well-functioning pelvic floor can build a structural support for the bladder and the urethra. Postpartum pelvic floor muscle training has been demonstrated to be effective in the prevention and treatment of stress urinary incontinence in the immediate postpartum period. The results also showed that the success of postpartum pelvic floor muscle exercise depended on training frequency and intensity of effort.
Pelvic floor muscle exercises are also called Kegel exercises after Dr. Arnold Kegel, who in the late 1940's, promoted them to strengthen the pelvic floor muscles. The muscles involved in PFME strengthening are the Levator Ani, which include the pubococcygeus, pubovaginalis, puborectalis, iliococcygeus, and also the iliococcygeus muscles collectively these muscles are referred to as the “deep muscles” of the pelvic floor complex. These muscles contract and relax under patient's command allowing the storage and discharge at a socially acceptable time and place, of both urine and faeces. PFME will also activate the “superficial muscles”, including ischiocavernosus, bulbospongiousus, the transverse peroneii and the urethral sphincters. Regular exercise is necessary to increase function. Muscle activation promotes function.
Such exercises require the relevant muscles to be contracted and relaxed regularly during the course of a day or over a period of many weeks, often months. A known aid for such exercises comprises a pre-formed core of rigid plastics material. Such aids are provided in a set of graded weights, requiring the (female) patient to insert them into the vagina, and retain them in position. However, this can be difficult for some women. The smallest available weight may be too heavy, or the size is incorrect. For many women the correct positioning of the device is problematic. These devices are not suitable for use by women with moderate or severe genitor-urinary prolapse.
A variety of non-surgical approaches have been investigated as treatments of urinary incontinence, including PFME, biofeedback, other behavioral therapies, and pelvic floor stimulation. Pelvic floor stimulation (PFS) involves the electrical stimulation of pelvic floor muscles using a probe or skin electrodes wired to a device for controlling the electrical stimulation. It is thought that pelvic floor stimulation via the pudendal nerve and nerve to the Levator Ani will improve urethral closure by activating the pelvic floor musculature. In addition, PFS is thought to improve partially denervated urethral and pelvic floor musculature by enhancing the process of reinnervation. PFS is also thought to improve neuromuscular coordination for the patient enabling them to perform correct voluntary contractions in the future. Patients receiving PFS may undergo treatments in a physician's office or physical therapy facility, or patients may undergo initial training in a physician's office followed by home treatment with a rented or purchased pelvic floor stimulator.
Conventional electro-stimulation treatments for urinary and faecal incontinence require a patient to apply stimulation via an internal electrode or skin electrodes in electrical contact with the body. Electrical stimulation units for home or office use are programmed to deliver stimulation at pre-set frequencies. A conventional electro-stimulation system includes pulse generator housed in a portable battery box that is attached by an appropriate lead to an electrode.
The electro-stimulation systems conventionally use a drive signal to the electrode. Differing therapeutic effects are achieved using different drive signal types. Conventionally such stimulation systems allow for a variation of drive signal pulse width or frequency by the patient. However each such known portable stimulation system has electronics which are dedicated for providing a specific predetermined drive signal having a geometry and other characteristics matched to the intended therapeutic effect. Adjustment of the control signal is conventionally provided by electronic push switches and or rotational control knobs. Such switches and knobs can often be tampered with by the patient, and it is thus difficult for a medical practitioner prescribing electro-stimulation treatment to control the treatment when the patient is away from a clinic.
Other known electro-stimulators include microprocessor based units, but these have a problem that conventionally, specialised pre-programming equipment needs to be used at the clinic to set the signal parameters. Such equipment is expensive and often difficult to use.
In EP 0411632 there is described an expandable vaginal electrode that is adapted to be inserted into a woman's vagina and which is utilized with a controller external to the device and woman's body.
In WO 98/34677 there is described a tampon especially for women suffering from urinary incontinence that is made of sponge like material and is used in the wet state. The tampon is used with a non-insulated electrode and external control source to treat incontinence.
In NL 8902023 there is described an electro-stimulator for combating incontinence. The stimulator is rigid and self-contained.
Whilst there are various devices in the art and available commercially for the treatment of urinary and/or faecal incontinence there is a continuing need for new devices that offer effective treatment through effective contact of electrodes with muscles to be treated, that are comfortable and easy to use and which afford the possibility for the patient to self treat without medical intervention and/or without the guidance of a physician.